It was 24 years ago this week that Los Angeles police officers were filmed brutally beating Rodney King. Coinciding with a newly filmed fatal shooting involving LAPD officers, and the release of a federal report outlining racial discrimination within the Ferguson police department, for many the anniversary calls attention to how little has changed in patterns of racist and violent law enforcement in the United States.

But at the same time, it also highlights something that has changed: the role of video in documenting violence by state agents. And not just in this country, but around the world.

Among the thousands of videos we have featured on The Human Rights Channel, police brutality is one of the most commonly documented issues. In the past month alone, footage has prompted investigations into conduct of the Israeli military and the Brazilian police, in addition to the LAPD shooting. And in Jamaica, an investigation into a deadly security operation is noteworthy for the U.S. surveillance video that is not playing a role.

By examining these recent cases, we can identify some of the ways video is indeed making a difference, and the existing challenges to using video effectively to expose abuse and bring about justice. (Click here for a reflection on the anniversary of the Rodney King beating by WITNESS’s Executive Director Yvette Alberdingk-Thijm.)

Unlike the beating of Rodney King–filmed on one witness’s camera–numerous videos have already emerged documenting Sunday’s shooting on skid row. There was the bystander whose Facebook clip was on the news that same day. By Monday, footage from a nearby security camera was released, and the mayor confirmed that two officers were wearing body cameras.

Video still from citizen footage of the LAPD shooting, February 28, 2015.

As each piece of footage emerges, it becomes more clear how limited any single video can be. The video of Rodney King’s beating, for example, was used by both the prosecutor and defence in the trials of officers involved. Multiple perspectives paint a fuller picture of the context, and leave less up to the imagination. Or that’s at least what we would hope. Still, studies have shown that regardless of what a video documents, viewers will interpret it in accordance with their existing biases.

New Gatekeepers of Video

The video of King’s beating–taken well before YouTube and social media–took days to get an audience. George Holliday, the witness who filmed it with his newly purchased handycam, took his tape to the police, then the local TV news. Last Sunday’s shooting came to our attention much more quickly. The bystander’s Facebook page served as its biggest initial distributor.

In the last few months, the social media company has made clear its intention to expand video on its platform, and this clip illustrated how quickly video can spread on the site, reaching millions of users within 24 hours. But it also highlighted the challenges of thinking of social platforms as archives for sharing, finding, and storing video.

By Tuesday, the original video posting could not be viewed at all on Facebook, an example of how ephemeral online video can be, even if it does provides potential evidence for a developing news story or criminal investigation.

West Bank: Despite soldiers’ helmet cams, a canine assault is not investigated until Facebook video makes the news

The same day footage of the LAPD shooting appeared in U.S. papers, another Facebook video caught the attention of Israeli media. The 15-second clip shows a Palestinian teenager attacked by dogs held by Israeli Defense Force (IDF) soldiers, who can be heard egging the dogs on, saying “Bite him.”

The footage had been posted to the Facebook page of an Israeli politician, but has since been removed. The IDF denounced the action of soldiers shown in the clip, and stated that it opened an internal investigation. “Upon completion of this inquiry, conclusions will be drawn and the necessary steps will be taken to prevent such incidents from recurring.”

But the Israeli human rights organization, B’tselem, responded with skepticism. The organization, which uses video to monitor human rights violations in the Palestinian territories, had spoken out about the incident shortly after it occurred last December. At the time, B’tselem shared a video that showed soldiers with dogs take the 16-year-old boy away, but did not capture the canine assault. The group has documented several incidents of soldiers setting dogs upon unarmed civilians, but has never received a satisfactory official response from the IDF.

As B’tselem pointed out this week, the newly released footage shows that both of the dog handlers were wearing helmet cameras, “and the footage captured on them was presumably available to their commanders during the routine debriefing held after such operations.”

Despite B’tselem’s previous calls for an investigation, and despite helmet cameras worn by the soldiers involved, it took a social media leak and a front-page story for this assault to be investigated by Israeli authorities.

Rio de Janeiro: Cellphone video posthumously exculpates 15-year-old after he is shot dead by police

On February 21, military police raided the favela of Palmerinha north of Rio de Janeiro, killing 15-year-old Alan de Souza Lima and leaving a 19-year-old injured with a bullet to the chest. Police said the shootings happened as their vehicle came under attack by four armed men.

A video still from cell phone after moments following the shooting.

And then a video emerged. The victim, Lima, had been filming his group of friends standing on the street telling jokes when police began running towards them, firing. (Click here for an article and to watch the disturbing footage.)

Once the video was released, clearly contradicting official accounts, the head of the military police said that the nine officers involved would be investigated. According to local media, in January alone, 64 people were killed by the military police in Rio de Janeiro. This case is representative of widespread allegations of police planting evidence or falsifying reports to justify unlawful killings. As reported recently in the New York Times, many favela residents are taking up cameras to expose such tactics.

Kingston: Lack of video evidence in investigation into a deadly 2010 raid

It can be easy to forget, considering the examples above, that in most cases of state violence, video evidence does not exist or is not released to bring abuses to light. There may be a lack of cameras or internet access in the region, government control of communications, or the targeting of filmers by authorities.

In Jamaica, an investigation into a deadly police raid is notable less for the video that has been used than for the video that is not available. A commission of enquiry is looking into a military operation in West Kingston in May of 2010 that left more than 74 civilians dead. Residents have described to the media, investigators, and the commission that soldiers went door to door taking young men, and executed civilians on the spot. (Full disclosure: I worked with Jamaicans for Justice in 2010 and documented the aftermath of the raid.)

But while security forces have provided video to the commission showing civilians fortify the neighborhood, no videos from residents have emerged to shine light on the operation. That may be because, as reported in a 2011 New Yorker article, residents’ cell phones were confiscated by soldiers.

The article also revealed that a U.S. surveillance plane took live video of the operation. It took a federal lawsuit for reporter Mattathias Schwartz to obtain six hours of footage from that plane from the U.S. Drug Enforcement Administration. Schwartz wrote, in 2013, “There is very little in the videos to support the Jamaican Army’s claim that ‘the resistance we faced in entering Tivoli Gardens was fierce,’ as reported by the Times in the days after the attack.”

With a commission of enquiry currently underway, Schwartz and others have urged commissioners to press the U.S. government to turn over information it has about the operation, including video footage. With several weeks left before the commission concludes, it is unclear if the U.S. will play a role, and if its surveillance video will help Jamaicans understand what happened during the deadly operation.

Ubiquitous AND accessible video

At a time when U.S. law enforcement agencies are considering implementing body cams as one way to curb abuses of power, these cases provide a lesson in the potential and limitations of more footage. We may live in an age of ubiquitous video, but the potential for that video to expose abuse and prompt investigations is not guaranteed.

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